For improving the production efficiency of connecting rods by optimizing the shot peening process,the arc height values of Almen test pieces under different processes were tested,the saturation curves of the shot peening processes were drawn,and finally,the optimum shot peening process was determined according to the Almen 10% theory.The microhardness,surface roughness and residual compressive stress of the sample under the optimal peening process were investigated.Results showed that after shot peening,the hardness of the sample was improved from the original 334 HV to 408 HV,the surface roughness increased from 0.26 μm to 2.68 μm,the residual compressive stress gradually decreased from the surface to the core,and the highest residual compressive stress on the surface was-554 MPa.When shot peened under the optimal process conditions,the connecting rod could meet the technical requirements.